dcw@ecsvax.UUCP (Douglas C. Wilson) (08/05/87)
We have just brought up ULTRIX 2.0 on a Vaxstation II. There has been a change made in the way MSCP devices are identified by the uda driver. In ULTRIX 1.2 partition tables were easily added to the driver by inserting the appropriate data into "struct size" in /sys/data/uda_data.c and then inserting the last two digits of the MSCP device identifier into the structure radfpt[]. For example for the RD54 drive the line in radfpt looked like: 54, rd54_sizes, /* RD54 disk drive */ I added a line for an Iomega Bernoulli drive on an Emulex SCSI controller 10, im10_sizes, /* IM10 disk drive */ This worked great for 1.2. In version 2.0 the radfpt[] structure has been changed to include further info for identification of the device. 0x25644036, rd54_sizes, ... I have figured out the last 5 hex digits from comparing the drives listed. 44= ascii "D" for the rD drive 036 = 54 since it is a "54" drive What are the first 3 digits, 256. They are different for a number of the drives listed in the table. A number of choices for my IM10 drive fail to allow the driver to identify the drive. HELP!! Douglas C. Wilson dcw@ecsvax Dept. of Chemistry University of NC Chapel Hill, NC 27514 -- Douglas C. Wilson dcw@ecsvax Dept. of Chemistry University of NC Chapel Hill, NC 27514
chris@mimsy.UUCP (Chris Torek) (08/06/87)
In article <3653@ecsvax.UUCP> dcw@ecsvax.UUCP (Douglas C. Wilson) writes: > 0x25644036, rd54_sizes, ... > I have figured out the last 5 hex digits from comparing the drives listed. > 44= ascii "D" for the rD drive > 036 = 54 since it is a "54" drive You are on the right track, but the encoding is not ASCII. The magic number 0x25644036 is the `media ID' as returned by Get Unit Status commands. It is made up of five 5-bit fields and one 7-bit field. The 5-bit fields encode either a blank (0) or one uppercase letter in A..Z (1-26); 0x25644036 expands to `DU' `RD '. The last seven bits represent the drive number, here 54. Since RA81s are `DU' `RA ' 81, I get 0x25641051. I do not know why DEC uses this media ID field instead of the (more sensible to me) drive type identifier also found in Get Unit Status end messages. -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690) Domain: chris@mimsy.umd.edu Path: seismo!mimsy!chris